16
Copyright © 2008 Lippincott Williams & Wilkins. Chapter 50 Assessment of Immune Function
Copyright © 2008 Lippincott Williams & Wilkins.
Chapter 50
Assessment of Immune Function
Chapter 50
Assessment of Immune Function
Copyright © 2008 Lippincott Williams & Wilkins.
The Immune SystemThe Immune System
• Immunity: the body’s specific protective response to invading foreign agent or organism
• Immunopathology: the study of diseases that result from dysfunction of the immune system
• Immune disorders: see Table 50-1
– Automimmunity
– Hypersensitivty
– Gammopathies
– Immune deficiencies: primary and secondary
Copyright © 2008 Lippincott Williams & Wilkins.
Central and Peripheral Lymphoid Organs Central and Peripheral Lymphoid Organs
Copyright © 2008 Lippincott Williams & Wilkins.
Development of Cells of the Immune System
Development of Cells of the Immune System
Copyright © 2008 Lippincott Williams & Wilkins.
LymphocytesLymphocytes• B lymphocytes mature in the bone marrow; T
lymphocytes mature in the thymus where they also differentiate into cells with various functions
Copyright © 2008 Lippincott Williams & Wilkins.
Immune FunctionImmune Function• Natural immunity: nonspecific response to any foreign
invader
– White blood cell action: release cell mediators such as histamine, bradykinin, and prostaglandins, and engulf (phagocytize) foreign substances
– Inflammatory response
– Physical barriers, such as intact skin, chemical barriers, and acidic gastric secretions or enzymes in tears and saliva
• Acquired immunity: specific against a foreign antigen
– Result of prior exposure to an antigen
– Active or passive
Copyright © 2008 Lippincott Williams & Wilkins.
Stages of Immune ResponseStages of Immune Response
Copyright © 2008 Lippincott Williams & Wilkins.
DefensesDefenses
• Phagocytic immune response
• Humoral or antibody response
• Cellular immune response
Copyright © 2008 Lippincott Williams & Wilkins.
Role of AntibodiesRole of Antibodies
• Agglutination of antigens
• Opsonization
• Promote release of vasoactive substances; activation of complement system and phagocytosis
• Act in concert with other components of the immune system
• Types of immunoglobulins: IgA, IgD, IgE,IgG, and IgM
Copyright © 2008 Lippincott Williams & Wilkins.
Antibody MoleculeAntibody Molecule
Copyright © 2008 Lippincott Williams & Wilkins.
Antigen–Antibody BindingAntigen–Antibody Binding
Copyright © 2008 Lippincott Williams & Wilkins.
Cellular Immune ResponseCellular Immune Response
• B lymphocytes: humoral immunity
– Produce antibodies or immunoglobulins
• T lymphocytes: cellular immunity
– Attack invaders directly, secrete cytokines, and stimulate immune system responses
– Helper T cells
– Cytotoxic T cells
– Memory cells
– Suppressor T cells (suppress immune response)
Copyright © 2008 Lippincott Williams & Wilkins.
Non-T and Non-B Lymphocytes Involved in Immune Response Non-T and Non-B Lymphocytes Involved in Immune Response
• Null cells
– Destroy antigen coated with antibody
• Natural killer cells
– Defend against microorganisms and some malignant cells
Copyright © 2008 Lippincott Williams & Wilkins.
Complement-Mediated Immune ResponsesComplement-Mediated Immune Responses
Copyright © 2008 Lippincott Williams & Wilkins.
Variables That Affect Immune System Function
Variables That Affect Immune System Function
• Age and gender
• Nutrition
• Presence of conditions and disorders: cancer/neoplasm, chronic illness, autoimmune disorders, surgery/trauma
• Allergies
• History of infection and immunization
• Genetic factors
• Lifestyle
• Medications and transfusions: see Table 50-6
• Pyschoneuroimmunologic factors
Copyright © 2008 Lippincott Williams & Wilkins.
Tests to Evaluate Immune FunctionTests to Evaluate Immune Function
• WBC count and differential
• Bone marrow biopsy
• Humoral and cellular immunity tests
• Phagocytic cell function test
• Complement component tests
• Hypersensitivty tests
• Specific antigen–antibody tests
• HIV infection tests
• See Chart 50-3
